Table of contents
Global Positioning System...…………….2
GPS Navigation Devices…………………..5
he Global Positioning System (GPS) is a space-based global
navigation satellite system that provides reliable location and
time information in all weather and at all times and anywhere
on or near the Earth when and where there is an unobstructed line of
sight to four or more GPS satellites. It is maintained by the United
States government and is freely accessible by anyone with a GPS
The Global Positioning System (GPS) is a U.S. space-based
radionavigation system that provides reliable positioning, navigation,
and timing services to civilian users on a continuous worldwide basis - freely available to all. For anyone with a GPS receiver, the system
will provide location and time. GPS provides accurate location and
time information for an unlimited number of people in all weather, day
and night, anywhere in the world. The GPS is made up of three parts:
satellites orbiting the Earth; control and monitoring stations on Earth;
and the GPS receivers owned by users. GPS satellites broadcast
signals from space that are picked up and identified by GPS receivers.
Each GPS receiver then provides three-dimensional location (latitude,
longitude, and altitude) plus the time.
GPS satellites provide service to civilian and military users. The
civilian service is freely available to all users on a continuous,
worldwide basis. The military service is available to U.S. and allied
armed forces as well as approved Government agencies.A variety of
GPS augmentation systems and techniques are available to enhance
system performance to meet specific user requirements. These
improve signal availability, accuracy, and integrity, allowing even
better performance than is possible using the basic GPS civilian
service.The outstanding performance of GPS over many years has
earned the confidence of millions of civil users worldwide. It has
proven its dependability in the past and promises to be of benefit to
users, throughout the world, far into the future.
Global Position System
lobal Positioning System (GPS) is a satellite based navigation
system that helps to find the location or position on the
Earth.Official name of GPS is Navigational Satellite Timing And
Ranging Global Positioning System (NAVSTAR GPS).
and was originally run
with 24 satellites.
It was established in 1973 to
limitations of previous navigation
Pentagon building near Washington, D.C., and has three major
components — the Departments of the Army, Navy, and Air Force
rovides reliable location and time information in all weather
and at all times and anywhere on or near the Earth.GPS
processed in a GPS receiver, enabling the receiver to compute
position, velocity, and time.
Four GPS satellite signals are used to compute positions in three
dimensions and the time offset in the receiver clock.
WHY DO WE NEED GPS
e need a powerful system such GPS because GPS can
provide accurate information and cover wide area.
In other words, all GPS devices can answer the question
"Where am I?", and may also be able to answer:
which roads or paths are available to me now?
which roads or paths should I take in order to get my desired
if some roads are usually busy at this time or are busy right now,
what would be a better route to take?
where can I get something to eat nearby or where can I get fuel
for my vehicle?
WHO CAN USED
PS operates in the UHF band.Each navigation satellite
transmits a unique UHF signal.The receiver pairs itself to
this transmission and determines the time difference
between the satellite clock and the receiver clock.The time
difference multiplied by the speed of light gives the receiver
distance from the satellite.
Signals from multiple satellites are used to fix the receivers
position in space.
There are two types of services available:
1. For Civilian/Research Use Standard Positioning System
L1 (1575.42 MHz), L2 (1227.60 MHz), L5 (1176.45 MHz) – For
L4 (1379.913 MHz) – For Research
2. For Military Use Precise Positioning System
L3 (1381.05 MHz)
GPS NAVIGATION DEVICES
GPS navigation device is any device that receives Global
Positioning System (GPS) signals for the purpose of determining
the device's current location on Earth. GPS devices provide
latitude and longitude information, and some may also calculate
altitude, although this is not considered sufficiently accurate or
continuously available enough (due to the possibility of signal
blockage and other factors) to rely on exclusively to pilot aircraft. GPS
devices are used in military, aviation, marine and consumer product
GPS devices may also have additional capabilities such as:
containing maps, which may be displayed in human readable
format via text or in a graphical format
providing suggested directions to a human in charge of a vehicle
or vessel via text or speech
providing directions directly to an autonomous vehicle such as a
providing information on traffic conditions (either via historical or
real time data) and suggesting alternative directions
providing information on nearby amenities such as restaurants,
fueling stations, etc.
mproved approaches to airports, which significantly increase
operational benefits and safety, are now being implemented even
at remote locations where traditional ground-based services are
unavailable. In some regions of the world, satellite signals are
augmented, or improved for special aviation applications, such as
landing planes during poor visibility conditions. In those cases, even
greater precision operations are possible.
Continuous, reliable, and accurate positioning information for all phases of flight on a global
basis, freely available to all.
Safe, flexible, and fuel-efficient routes for airspace service providers and airspace users.
Potential decommissioning and reduction of expensive ground based navigation facilities,
systems, and services.
Increased safety for surface movement operations made possible by situational awareness.
Reduced aircraft delays due to increased capacity made possible through reduced separation
minimums and more efficient air traffic management, particularly during inclement weather.
Increased safety-of-life capabilities such as EGPWS
The good news for the aviation community is that GPS is being
constantly improved and modernized. A main component of the
ongoing civilian modernization effort is the addition of two new
signals. These signals complement the existing civilian service. The
first of these new signals is for general use in non-safety critical
applications. The second new signal will be internationally protected
for aviation navigational purposes. This additional safety-of-life civilian
signal will make GPS an even more robust navigation service for many
viators throughout the world use the Global Positioning System
(GPS) to increase the safety and efficiency of flight. With its
accurate, continuous, and global capabilities, GPS offers
seamless satellite navigation services that satisfy many of the
requirements for aviation users. Space-based position and navigation
enables three-dimensional position determination for all phases of
flight from departure, en route, and arrival, to airport surface
The trend toward an Area Navigation concept means a greater
role for GPS. Area Navigation allows aircraft to fly user-preferred
routes from waypoint to waypoint, where waypoints do not depend on
ground infrastructure. Procedures have been expanded to use GPS and
augmented services for all phases of flight. This has been especially
true in areas that lack suitable ground based navigation aids or
New and more efficient air routes made possible by GPS are
continuing to expand. Vast savings in time and money are being
realized. In many cases, aircraft flying over data-sparse areas such as
oceans have been able to safely reduce their separation between one
another, allowing more aircraft to fly more favorable and efficient
routes, saving time, fuel, and increasing cargorevenue.
“Ten of the major airports here in the Democratic Republic of the Congo now have the added
capability of GPS approaches and departures. The satellite-based navigation system we are using is not
dependent on expensive ground-based navigational aides, and it increases the safety and efficiency of
-Chris O'Brien, Deputy Chief of Aviation, MONUC/ICAO
Project, Democratic Republic of the Congo-
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